Sorrow

Old wives tales say that whenever a tear is shed a Sorrow is born. Glowing softly in the mists, Sorrows float silently, moving to a gentle lullaby only they can hear. However, when they sense grief their languid motion becomes a frenzy. Darting and diving they swirl around the source of grief, ghostly faery fire lancing into the victim, intensifying their woe - birthing new Sorrows. The frenzy only stopping when the victim sheds its last tear.

The full reason of the Sorrow is for Weep: if the Sorrow inflicts a Wound it spawns another Sorrow adjacent to that model. They also have Fly and aren't super-weak, but struggle to inflict reliable Wounds - and those extra Sorrows are often just more Loot to the Heroes.